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Stylianakis I, Zervos N, Lii JH, Pantazis DA, Kolocouris A. Conformational energies of reference organic molecules: benchmarking of common efficient computational methods against coupled cluster theory. J Comput Aided Mol Des 2023; 37:607-656. [PMID: 37597063 PMCID: PMC10618395 DOI: 10.1007/s10822-023-00513-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 06/03/2023] [Indexed: 08/21/2023]
Abstract
We selected 145 reference organic molecules that include model fragments used in computer-aided drug design. We calculated 158 conformational energies and barriers using force fields, with wide applicability in commercial and free softwares and extensive application on the calculation of conformational energies of organic molecules, e.g. the UFF and DREIDING force fields, the Allinger's force fields MM3-96, MM3-00, MM4-8, the MM2-91 clones MMX and MM+, the MMFF94 force field, MM4, ab initio Hartree-Fock (HF) theory with different basis sets, the standard density functional theory B3LYP, the second-order post-HF MP2 theory and the Domain-based Local Pair Natural Orbital Coupled Cluster DLPNO-CCSD(T) theory, with the latter used for accurate reference values. The data set of the organic molecules includes hydrocarbons, haloalkanes, conjugated compounds, and oxygen-, nitrogen-, phosphorus- and sulphur-containing compounds. We reviewed in detail the conformational aspects of these model organic molecules providing the current understanding of the steric and electronic factors that determine the stability of low energy conformers and the literature including previous experimental observations and calculated findings. While progress on the computer hardware allows the calculations of thousands of conformations for later use in drug design projects, this study is an update from previous classical studies that used, as reference values, experimental ones using a variety of methods and different environments. The lowest mean error against the DLPNO-CCSD(T) reference was calculated for MP2 (0.35 kcal mol-1), followed by B3LYP (0.69 kcal mol-1) and the HF theories (0.81-1.0 kcal mol-1). As regards the force fields, the lowest errors were observed for the Allinger's force fields MM3-00 (1.28 kcal mol-1), ΜΜ3-96 (1.40 kcal mol-1) and the Halgren's MMFF94 force field (1.30 kcal mol-1) and then for the MM2-91 clones MMX (1.77 kcal mol-1) and MM+ (2.01 kcal mol-1) and MM4 (2.05 kcal mol-1). The DREIDING (3.63 kcal mol-1) and UFF (3.77 kcal mol-1) force fields have the lowest performance. These model organic molecules we used are often present as fragments in drug-like molecules. The values calculated using DLPNO-CCSD(T) make up a valuable data set for further comparisons and for improved force field parameterization.
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Affiliation(s)
- Ioannis Stylianakis
- Department of Medicinal Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15771, Athens, Greece
| | - Nikolaos Zervos
- Department of Medicinal Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15771, Athens, Greece
| | - Jenn-Huei Lii
- Department of Chemistry, National Changhua University of Education, Changhua City, Taiwan
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Antonios Kolocouris
- Department of Medicinal Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15771, Athens, Greece.
- Laboratory of Medicinal Chemistry, Section of Pharmaceutical Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, 15771, Athens, Greece.
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Roy N, Das R, Paira R, Paira P. Different routes for the construction of biologically active diversely functionalized bicyclo[3.3.1]nonanes: an exploration of new perspectives for anticancer chemotherapeutics. RSC Adv 2023; 13:22389-22480. [PMID: 37501776 PMCID: PMC10369265 DOI: 10.1039/d3ra02003g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/09/2023] [Indexed: 07/29/2023] Open
Abstract
Cancer is the second most high-morbidity disease throughout the world. From ancient days, natural products have been known to possess several biological activities, and research on natural products is one of the most enticing areas where scientists are engrossed in the extraction of valuable compounds from various plants to isolate many life-saving medicines, along with their other applications. It has been noticed that the bicyclo[3.3.1]nonane moiety is predominant in most biologically active natural products owing to its exceptional characteristics compared to others. Many derivatives of bicyclo[3.3.1]nonane are attractive to researchers for use in asymmetric catalysis or as potent anticancer entities along with their successful applications as ion receptors, metallocycles, and molecular tweezers. Therefore, this review article discusses several miscellaneous synthetic routes for the construction of bicyclo[3.3.1]nonanes and their heteroanalogues in association with the delineation of their anticancer activities with few selective compounds.
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Affiliation(s)
- Nilmadhab Roy
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology Vellore 632014 Tamilnadu India
- Department of Chemistry, Maharaja Manindra Chandra College 20 Ramkanto Bose Street Kolkata 700 003 India
| | - Rishav Das
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology Vellore 632014 Tamilnadu India
- Department of Chemistry, Maharaja Manindra Chandra College 20 Ramkanto Bose Street Kolkata 700 003 India
| | - Rupankar Paira
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology Vellore 632014 Tamilnadu India
- Department of Chemistry, Maharaja Manindra Chandra College 20 Ramkanto Bose Street Kolkata 700 003 India
| | - Priyankar Paira
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology Vellore 632014 Tamilnadu India
- Department of Chemistry, Maharaja Manindra Chandra College 20 Ramkanto Bose Street Kolkata 700 003 India
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Lee A, Yang JH, Oh JH, Hay BP, Lee K, Lynch VM, Sessler JL, Kim SK. Cyclo[2]carbazole[2]pyrrole: a preorganized calix[4]pyrrole analogue. Chem Sci 2023; 14:1218-1226. [PMID: 36756337 PMCID: PMC9891360 DOI: 10.1039/d2sc06376j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022] Open
Abstract
A cyclo[2]carbazole[2]pyrrole (2) consisting of two carbazoles and two pyrroles has been synthesized by directly linking the carbazole 1- and 8-carbon atoms to the pyrrole α-carbon atoms. Macrocycle 2 is an extensively conjugated 16-membered macrocyclic ring that is fixed in a pseudo-1,3-alternate conformation. This provides a preorganized anion binding site consisting of two pyrrole subunits. 1H NMR spectroscopic analysis revealed that only the two diagonally opposed pyrrole NH protons, as opposed to the carbazole protons, take part in anion binding. Nevertheless, cyclo[2]carbazole[2]pyrrole 2 binds representative anions with higher affinity in CD2Cl2 than calix[4]pyrrole (1), a well-studied non-conjugated tetrapyrrole macrocycle that binds anions via four pyrrolic NH hydrogen bond interactions. On the basis of computational studies, the higher chloride anion affinity of receptor 2 relative to 1 is rationalized in terms of a larger binding energy and a lower host strain energy associated with anion complexation. In the presence of excess fluoride or bicarbonate anions, compound 2 loses two pyrrolic NH protons to produce a stable dianionic macrocycle [2-2H]2- displaying a quenched fluorescence.
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Affiliation(s)
- Areum Lee
- Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University Jinju-si Gyeongsangnam-do 52828 Korea
| | - Ju Ho Yang
- Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University Jinju-si Gyeongsangnam-do 52828 Korea
| | - Ju Hyun Oh
- Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University Jinju-si Gyeongsangnam-do 52828 Korea
| | | | - Kyounghoon Lee
- Department of Chemistry Education and Research Institute of Natural Science, Gyeongsang National UniversityJinju52828Korea
| | - Vincent M. Lynch
- Department of Chemistry, The University of Texas at Austin105 E. 24th, Street-Stop A5300AustinTexas 78712-1224USA
| | - Jonathan L. Sessler
- Department of Chemistry, The University of Texas at Austin105 E. 24th, Street-Stop A5300AustinTexas 78712-1224USA
| | - Sung Kuk Kim
- Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University Jinju-si Gyeongsangnam-do 52828 Korea
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4
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Lewis-Atwell T, Townsend PA, Grayson MN. Comparisons of different force fields in conformational analysis and searching of organic molecules: A review. Tetrahedron 2021. [DOI: 10.1016/j.tet.2020.131865] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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5
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Hwang SB, Lee CJ, Lee S, Ma S, Kang YM, Cho KH, Kim SY, Kwon OY, Yoon CN, Kang YK, Yoon JH, Nam KY, Kim SG, In Y, Chai HH, Acree WE, Grant JA, Gibson KD, Jhon MS, Scheraga HA, No KT. PMFF: Development of a Physics-Based Molecular Force Field for Protein Simulation and Ligand Docking. J Phys Chem B 2020; 124:974-989. [PMID: 31939671 DOI: 10.1021/acs.jpcb.9b10339] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The physics-based molecular force field (PMFF) was developed by integrating a set of potential energy functions in which each term in an intermolecular potential energy function is derived based on experimental values, such as the dipole moments, lattice energy, proton transfer energy, and X-ray crystal structures. The term "physics-based" is used to emphasize the idea that the experimental observables that are considered to be the most relevant to each term are used for the parameterization rather than parameterizing all observables together against the target value. PMFF uses MM3 intramolecular potential energy terms to describe intramolecular interactions and includes an implicit solvation model specifically developed for the PMFF. We evaluated the PMFF in three ways. We concluded that the PMFF provides reliable information based on the structure in a biological system and interprets the biological phenomena accurately by providing more accurate evidence of the biological phenomena.
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Affiliation(s)
- Sung Bo Hwang
- Yonsei University , Department of Biotechnology , 50 Yonsei-ro , Seodaemun-gu, Seoul KR 120-479 , Republic of Korea
| | - Chang Joon Lee
- Dotmatic , Ace Gwanggyo Tower 1, 17 Daehak 4-Ro , Yeongtong-gu, Suwon , Gyeonggido 16226 , Republic of Korea
| | - Sehan Lee
- Molecular Design Team, New Drug Development Center , Daegu- Gyeongbuk Medical Innovation Foundation (DGMIF) , 41061 Daegu City , Republic of Korea
| | - Songling Ma
- Xtalpi-AI Research Center , Xtalpi Inc. , 1500-1, Hailong Building Z-Park , Bejing , China 100090
| | - Young-Mook Kang
- Korea Research Institute of Chemical Technology, Drug Information Platform Center , 141, Gajeong-ro , Yuseong-gu, Daejon 34114 , Republic of Korea
| | - Kwang Hwi Cho
- Department of Bioinformatics , Soongsil University , Seoul 156-743 , Republic of Korea
| | - Su-Yeon Kim
- School of Liberal Arts Education (Chemistry), College of Liberal Arts and Cross-Disciplinary Studies , University of Seoul , Seoul 02504 , Republic of Korea
| | - Oh Young Kwon
- Wooreebio Institute , 79 Seonggok-Ro , Danwon-Ku, Ansan-si 15409 , Republic of Korea
| | - Chang No Yoon
- Department of Neuroscience , Korea University of Science and Technology , Seoul 02792 , Republic of Korea
| | - Young Kee Kang
- Department of Chemistry , Chungbuk National University , Chungdae-ro 1 , Seowon-gu, Cheongju , Chungbuk 28644 , Republic of Korea
| | - Jeong Hyeok Yoon
- Research Center, Pharos I&BT Co., Ltd. , 1407 & 1408, 38, Heungan-daero 427beon-gil , Dongan-gu, Anyang 14059 , Republic of Korea
| | - Ky-Youb Nam
- Research Center, Pharos I&BT Co., Ltd. , 1407 & 1408, 38, Heungan-daero 427beon-gil , Dongan-gu, Anyang 14059 , Republic of Korea
| | - Seong-Gon Kim
- Korea Biopharm Co., LTD. , #C-430 Sigma 2 Office B/D, 164 Tancheonsang-ro , Bundang-gu, Seongnam-si 13631 , Republic of Korea
| | - Youngyong In
- Vovi C&E Co. Ltd. , 803-ho, 2497, Nambusunhwan-ro , Seocho-gu, Seoul 06724 , Republic of Korea
| | - Han Ha Chai
- National institute of animal science , ReDA, 1500, Kongjwipatjwi-ro , Iseo-myeon, Wanju-gun , Jeollabuk-do 55365 , Republic of Korea
| | - William E Acree
- Department of Chemistry , University of North Texas , 1155 Union Circle Drive #305070 , Denton , Texas 76230-5017 , United States
| | - J Andrew Grant
- Baker Laboratory of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Ken D Gibson
- Baker Laboratory of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Mu Shik Jhon
- Baker Laboratory of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Harold A Scheraga
- Baker Laboratory of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Kyoung Tai No
- Yonsei University , Department of Biotechnology , 50 Yonsei-ro , Seodaemun-gu, Seoul KR 120-479 , Republic of Korea.,Bioinformatics & Molecular Design Research Center , 50 Yonsei-ro , Seodaemun-gu, Seoul KR 120-479 , Republic of Korea
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6
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Uto T, Minamizaki M, Yui T. Molecular Dynamics Simulation of Cellulose I-Ethylenediamine Complex Crystal Models. J Phys Chem B 2020; 124:134-143. [PMID: 31794670 DOI: 10.1021/acs.jpcb.9b08153] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cellulose I fibrils swell on exposure to ethylenediamine (EDA), which forms the cellulose I-EDA complex. These are regarded as host materials with guest intercalation. The present study reports molecular dynamics (MD) simulations of cellulose I-EDA crystal models with finite fiber to reproduce desorption of EDA molecules. The force field parameters for EDA were improved. Part of the EDA molecules was desorbed only from the surfaces of the crystal models, not from their interiors. The EDA molecules diffused through a hydrophilic channel composed of the hydrophilic edges of the cellulose chains, and their conformations and orientations changed. With the configuration of the cellulose chains being held, the vacant hydrophilic channel was immediately filled with water molecules. The innermost part of the crystal models, defined as a core unit, was partly deformed from the initial crystal structure, including the changes in the exocyclic group conformations of the cellulose chains and the orientations of the EDA molecules, coupled with partial reconfiguration of the intermolecular hydrogen bonding scheme. A possible crystalline conversion scheme after complete desorption of EDA has been discussed based on the present findings.
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Affiliation(s)
- Takuya Uto
- Organization for Promotion of Tenure Track , University of Miyazaki , Nishi 1-1 Gakuen-Kibanadai , Miyazaki 889-2192 , Japan.,Department of Applied Chemistry, Faculty of Engineering , University of Miyazaki , Nishi 1-1 Gakuen-Kibanadai , Miyazaki 889-2192 , Japan
| | - Meguru Minamizaki
- Department of Applied Chemistry, Faculty of Engineering , University of Miyazaki , Nishi 1-1 Gakuen-Kibanadai , Miyazaki 889-2192 , Japan
| | - Toshifumi Yui
- Department of Applied Chemistry, Faculty of Engineering , University of Miyazaki , Nishi 1-1 Gakuen-Kibanadai , Miyazaki 889-2192 , Japan
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7
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Carroll AM, McCarthy M, Lacey PM, Saunders CP, Connolly DJ, Farrell A, Rokade BV, Goddard R, Fristrup P, Norrby PO, Guiry PJ. Synthetic and mechanistic studies in enantioselective allylic substitutions catalysed by palladium complexes of a modular class of axially chiral quinazoline-containing ligands. Tetrahedron 2020. [DOI: 10.1016/j.tet.2019.130780] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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8
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Wang RT, Xu AF, Chen JY, Yang LW, Xu G, Jarvis V, Britten JF. Reversing Organic-Inorganic Hybrid Perovskite Degradation in Water via pH and Hydrogen Bonds. J Phys Chem Lett 2019; 10:7245-7250. [PMID: 31689109 DOI: 10.1021/acs.jpclett.9b02972] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The moisture instability of organic-inorganic hybrid perovskite solar cells has been a major obstacle to the commercialization, calling for mechanistic understanding of the degradation process, which has been under debate. Here we present a surprising discovery that the degradation is actually reversible, via in situ observation of X-ray diffraction, supported by FTIR and SEM. To isolate the hydrogen bond effect, water was replaced by methanol during the in situ experiment, revealing the decomposition to be initiated by the breakdown of N-H-I hydrogen bonds. This is followed by the step of organic iodide hydrolyzing, which can be inhibited in the neutral environment, making the whole process reversible under variable pH.
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Affiliation(s)
- Ryan Taoran Wang
- Department of Materials Science and Engineering , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4L8 , Canada
| | - Alex Fan Xu
- Department of Materials Science and Engineering , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4L8 , Canada
| | - Jason Yuanzhe Chen
- Department of Materials Science and Engineering , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4L8 , Canada
| | - Lory Wenjuan Yang
- Department of Materials Science and Engineering , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4L8 , Canada
| | - Gu Xu
- Department of Materials Science and Engineering , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4L8 , Canada
| | - Victoria Jarvis
- MAX Diffraction Facility, Department of Chemistry , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4M1 , Canada
| | - James F Britten
- MAX Diffraction Facility, Department of Chemistry , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4M1 , Canada
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9
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Wahl J, Freyss J, von Korff M, Sander T. Accuracy evaluation and addition of improved dihedral parameters for the MMFF94s. J Cheminform 2019; 11:53. [PMID: 31392432 PMCID: PMC6686419 DOI: 10.1186/s13321-019-0371-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 07/23/2019] [Indexed: 11/10/2022] Open
Abstract
The Platinum dataset of protein-bound ligand conformations was used to benchmark the ability of the MMFF94s force field to generate bioactive conformations by minimization of randomly generated conformers. Torsion angle parameters that generally caused wrong geometries were reparameterized by conducting dihedral scans using ab initio calculations at the MP2 level. This reparameterization resulted in a systematic improvement of generated conformations.
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Affiliation(s)
- Joel Wahl
- Scientific Computing Drug Discovery, Idorsia Pharmaceuticals Ltd, Hegenheimermattweg 89, 4123 Allschwil, Switzerland
| | - Joel Freyss
- Global Information Systems, Idorsia Pharmaceuticals Ltd, Hegenheimermattweg 91, 4123 Allschwil, Switzerland
| | - Modest von Korff
- Scientific Computing Drug Discovery, Idorsia Pharmaceuticals Ltd, Hegenheimermattweg 89, 4123 Allschwil, Switzerland
| | - Thomas Sander
- Scientific Computing Drug Discovery, Idorsia Pharmaceuticals Ltd, Hegenheimermattweg 89, 4123 Allschwil, Switzerland
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10
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Sharapa DI, Genaev A, Cavallo L, Minenkov Y. A Robust and Cost‐Efficient Scheme for Accurate Conformational Energies of Organic Molecules. Chemphyschem 2018; 20:92-102. [DOI: 10.1002/cphc.201801063] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Dmitry I. Sharapa
- Institute of Catalysis Research and TechnologyKarlsruhe Institute of Technology (KIT) Hermann-von-Helmholtz Platz 1 Eggenstein-Leopoldshafen D-76344 Germany
| | - Alexander Genaev
- Vorozhtsov Novosibirsk Institute of Organic Chemistry Academician Lavrent'ev Ave., 9 Novosibirsk 630090 Russian Federation
| | - Luigi Cavallo
- KAUST Catalysis Center (KCC)King Abdullah University of Science and Technology Thuwal- 23955-6900 Saudi Arabia
| | - Yury Minenkov
- Moscow Institute of Physics and Technology Institutskiy Pereulok 9, Dolgoprudny Moscow Region 141700 Russia
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11
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Sam Paul D, Gautham N. Protein-small molecule docking with receptor flexibility in iMOLSDOCK. J Comput Aided Mol Des 2018; 32:889-900. [PMID: 30128925 DOI: 10.1007/s10822-018-0152-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 08/11/2018] [Indexed: 12/27/2022]
Abstract
We have earlier reported the iMOLSDOCK technique to perform 'induced-fit' peptide-protein docking. iMOLSDOCK uses the mutually orthogonal Latin squares (MOLSs) technique to sample the conformation and the docking pose of the small molecule ligand and also the flexible residues of the receptor protein, and arrive at the optimum pose and conformation. In this paper we report the extension carried out in iMOLSDOCK to dock nonpeptide small molecule ligands to receptor proteins. We have benchmarked and validated iMOLSDOCK with a dataset of 34 protein-ligand complexes as well as with Astex Diverse dataset, with nonpeptide small molecules as ligands. We have also compared iMOLSDOCK with other flexible receptor docking tools GOLD v5.2.1 and AutoDock Vina. The results obtained show that the method works better than these two algorithms, though it consumes more computer time. The source code and binary of MOLS 2.0 (under a GNU Lesser General Public License) are freely available for download at https://sourceforge.net/projects/mols2-0/files/ .
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Affiliation(s)
- D Sam Paul
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai, 600025, India
| | - N Gautham
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai, 600025, India.
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12
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Sato K, Pradhan E, Asahi R, Akimov AV. Charge transfer dynamics at the boron subphthalocyanine chloride/C60 interface: non-adiabatic dynamics study with Libra-X. Phys Chem Chem Phys 2018; 20:25275-25294. [DOI: 10.1039/c8cp03841d] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The Libra-X software for non-adiabatic molecular dynamics is reported. It is used to comprehensively study the charge transfer dynamics at the boron subphtalocyanine chloride (SubPc)/fullerene (C60) interface.
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Affiliation(s)
- Kosuke Sato
- Toyota Central Research and Development Laboratories, Inc
- Nagakute
- Japan
| | - Ekadashi Pradhan
- Department of Chemistry
- University at Buffalo
- The State University of New York
- New York 14260-3000
- USA
| | - Ryoji Asahi
- Toyota Central Research and Development Laboratories, Inc
- Nagakute
- Japan
| | - Alexey V. Akimov
- Department of Chemistry
- University at Buffalo
- The State University of New York
- New York 14260-3000
- USA
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13
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Zahariev F, De Silva N, Gordon MS, Windus TL, Dick-Perez M. ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data. J Chem Inf Model 2017; 57:391-396. [PMID: 28169538 DOI: 10.1021/acs.jcim.6b00654] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides, important for metal extraction chemistry, are parametrized using ParFit. ParFit is in an open source program available for free on GitHub ( https://github.com/fzahari/ParFit ).
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Affiliation(s)
- Federico Zahariev
- Department of Chemistry and Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States
| | - Nuwan De Silva
- Department of Chemistry and Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States
| | - Mark S Gordon
- Department of Chemistry and Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States
| | - Theresa L Windus
- Department of Chemistry and Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States
| | - Marilu Dick-Perez
- Department of Chemistry and Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States
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14
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Ji H, Jung Y. Artificial neural network for the configuration problem in solids. J Chem Phys 2017; 146:064103. [DOI: 10.1063/1.4974928] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Hyunjun Ji
- Graduate School of EEWS, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Yousung Jung
- Graduate School of EEWS, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
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15
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Jia WZ, Cheng F, Zhang YJ, Ge JY, Yao SQ, Zhu Q. Rapid synthesis of flavone-based monoamine oxidase (MAO) inhibitors targeting two active sites using click chemistry. Chem Biol Drug Des 2016; 89:141-151. [DOI: 10.1111/cbdd.12841] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 05/29/2016] [Accepted: 08/13/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Wei Zhen Jia
- Institute of Bioengineering; Zhejiang University of Technology; Zhejiang China
| | - Feng Cheng
- Institute of Bioengineering; Zhejiang University of Technology; Zhejiang China
| | - Yin Jun Zhang
- Institute of Bioengineering; Zhejiang University of Technology; Zhejiang China
| | - Jin Yan Ge
- Institute of Bioengineering; Zhejiang University of Technology; Zhejiang China
| | - Shao Q. Yao
- Department of Chemistry; National University of Singapore; Singapore Singapore
| | - Qing Zhu
- Institute of Bioengineering; Zhejiang University of Technology; Zhejiang China
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Janowski PA, Moriarty NW, Kelley BP, Case DA, York DM, Adams PD, Warren GL. Improved ligand geometries in crystallographic refinement using AFITT in PHENIX. Acta Crystallogr D Struct Biol 2016; 72:1062-72. [PMID: 27599738 PMCID: PMC5013598 DOI: 10.1107/s2059798316012225] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/27/2016] [Indexed: 11/24/2022] Open
Abstract
Modern crystal structure refinement programs rely on geometry restraints to overcome the challenge of a low data-to-parameter ratio. While the classical Engh and Huber restraints work well for standard amino-acid residues, the chemical complexity of small-molecule ligands presents a particular challenge. Most current approaches either limit ligand restraints to those that can be readily described in the Crystallographic Information File (CIF) format, thus sacrificing chemical flexibility and energetic accuracy, or they employ protocols that substantially lengthen the refinement time, potentially hindering rapid automated refinement workflows. PHENIX-AFITT refinement uses a full molecular-mechanics force field for user-selected small-molecule ligands during refinement, eliminating the potentially difficult problem of finding or generating high-quality geometry restraints. It is fully integrated with a standard refinement protocol and requires practically no additional steps from the user, making it ideal for high-throughput workflows. PHENIX-AFITT refinements also handle multiple ligands in a single model, alternate conformations and covalently bound ligands. Here, the results of combining AFITT and the PHENIX software suite on a data set of 189 protein-ligand PDB structures are presented. Refinements using PHENIX-AFITT significantly reduce ligand conformational energy and lead to improved geometries without detriment to the fit to the experimental data. For the data presented, PHENIX-AFITT refinements result in more chemically accurate models for small-molecule ligands.
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Affiliation(s)
- Pawel A. Janowski
- BioMaPs Institute, Center for Integrative Proteomics Research, Rutgers University, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Nigel W. Moriarty
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Brian P. Kelley
- Novartis Institutes for BioMedical Research Inc., Cambridge, MA 02139, USA
| | - David A. Case
- BioMaPs Institute, Center for Integrative Proteomics Research, Rutgers University, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Darrin M. York
- BioMaPs Institute, Center for Integrative Proteomics Research, Rutgers University, Piscataway, NJ 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Paul D. Adams
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720, USA
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Liu Z, Pottel J, Shahamat M, Tomberg A, Labute P, Moitessier N. Elucidating Hyperconjugation from Electronegativity to Predict Drug Conformational Energy in a High Throughput Manner. J Chem Inf Model 2016; 56:788-801. [DOI: 10.1021/acs.jcim.6b00012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Zhaomin Liu
- Department
of Chemistry, McGill University, 801 Sherbrooke St. W., Montréal, QC, Canada H3A 0B8
| | - Joshua Pottel
- Department
of Chemistry, McGill University, 801 Sherbrooke St. W., Montréal, QC, Canada H3A 0B8
| | - Moeed Shahamat
- Department
of Chemistry, McGill University, 801 Sherbrooke St. W., Montréal, QC, Canada H3A 0B8
| | - Anna Tomberg
- Department
of Chemistry, McGill University, 801 Sherbrooke St. W., Montréal, QC, Canada H3A 0B8
| | - Paul Labute
- Chemical Computing Group Inc., 1010 Sherbrooke St. W., Montréal, QC, Canada H3A 2R7
| | - Nicolas Moitessier
- Department
of Chemistry, McGill University, 801 Sherbrooke St. W., Montréal, QC, Canada H3A 0B8
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18
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Tosco P, Stiefl N, Landrum G. Bringing the MMFF force field to the RDKit: implementation and validation. J Cheminform 2014. [PMCID: PMC4116604 DOI: 10.1186/s13321-014-0037-3] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
A general purpose force field such as MMFF94/MMFF94s, which can properly deal with a
wide range of diverse structures, is very valuable in the context of a
cheminformatics toolkit. Herein we present an open-source implementation of this
force field within the RDKit. The new MMFF functionality can be accessed through a
C++/C#/Python/Java application programming interface (API) developed along the lines
of the one already available for UFF in the RDKit. Our implementation was fully
validated against the official validation suite provided by the MMFF authors. All
energies and gradients were correctly computed; moreover, atom type and force
constants were correctly assigned for 3D molecules built from SMILES strings. To
provide full flexibility, the available API provides direct access to include/exclude
individual terms from the MMFF energy expression and to carry out constrained
geometry optimizations. The availability of a MMFF-capable molecular mechanics engine
coupled with the rest of the RDKit functionality and covered by the BSD license is
appealing to researchers operating in both academia and industry.
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Schmidt TC, Paasche A, Grebner C, Ansorg K, Becker J, Lee W, Engels B. QM/MM investigations of organic chemistry oriented questions. Top Curr Chem (Cham) 2014; 351:25-101. [PMID: 22392477 DOI: 10.1007/128_2011_309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
About 35 years after its first suggestion, QM/MM became the standard theoretical approach to investigate enzymatic structures and processes. The success is due to the ability of QM/MM to provide an accurate atomistic picture of enzymes and related processes. This picture can even be turned into a movie if nuclei-dynamics is taken into account to describe enzymatic processes. In the field of organic chemistry, QM/MM methods are used to a much lesser extent although almost all relevant processes happen in condensed matter or are influenced by complicated interactions between substrate and catalyst. There is less importance for theoretical organic chemistry since the influence of nonpolar solvents is rather weak and the effect of polar solvents can often be accurately described by continuum approaches. Catalytic processes (homogeneous and heterogeneous) can often be reduced to truncated model systems, which are so small that pure quantum-mechanical approaches can be employed. However, since QM/MM becomes more and more efficient due to the success in software and hardware developments, it is more and more used in theoretical organic chemistry to study effects which result from the molecular nature of the environment. It is shown by many examples discussed in this review that the influence can be tremendous, even for nonpolar reactions. The importance of environmental effects in theoretical spectroscopy was already known. Due to its benefits, QM/MM can be expected to experience ongoing growth for the next decade.In the present chapter we give an overview of QM/MM developments and their importance in theoretical organic chemistry, and review applications which give impressions of the possibilities and the importance of the relevant effects. Since there is already a bunch of excellent reviews dealing with QM/MM, we will discuss fundamental ingredients and developments of QM/MM very briefly with a focus on very recent progress. For the applications we follow a similar strategy.
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Affiliation(s)
- Thomas C Schmidt
- Institut für Phys. und Theor. Chemie, Emil-Fischer-Strasse 42, Campus Hubland Nord, 97074, Würzburg, Germany
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20
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Hay BP, Jia C, Nadas J. Computer-aided design of host molecules for recognition of organic guests. COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2013.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Shojaei SHR, Vandenbussche J, Deleuze MS, Bultinck P. Electron momentum spectroscopy of 1-butene: a theoretical analysis using molecular dynamics and molecular quantum similarity. J Phys Chem A 2013; 117:8388-98. [PMID: 23902590 DOI: 10.1021/jp405122p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The results of experimental studies of the valence electronic structure of 1-butene by means of electron momentum spectroscopy (EMS) have been reinterpreted on the basis of molecular dynamical simulations in conjunction with the classical MM3 force field. The computed atomic trajectories demonstrate the importance of thermally induced nuclear dynamics in the electronic neutral ground state, in the form of significant deviations from stationary points on the potential energy surface and considerable variations of the C-C-C-C dihedral angle. These motions are found to have a considerable influence on the computed spectral bands and outer-valence electron momentum distributions. Euclidean distances between spherically averaged electron momentum densities confirm that thermally induced nuclear motions need to be fully taken into account for a consistent interpretation of the results of EMS experiments on conformationally flexible molecules.
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Affiliation(s)
- S H Reza Shojaei
- Research Group of Theoretical Chemistry and Molecular Modelling, Hasselt University, Agoralaan, Gebouw D, B-3590 Diepenbeek, Belgium
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22
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Galezowska A, Harrison MW, Herniman JM, Skylaris CK, Langley GJ. A predictive science approach to aid understanding of electrospray ionisation tandem mass spectrometric fragmentation pathways of small molecules using density functional calculations. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:964-970. [PMID: 23592198 DOI: 10.1002/rcm.6536] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/23/2013] [Accepted: 02/05/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Tandem mass spectrometry (MS/MS) dissociation pathways can vary markedly between compound classes and can result in challenging and time-consuming interpretation of the data. Compound, class and substructure specific fragmentation rules for protonated molecules require refinement to aid the structural elucidation process. METHODS The application of a predictive science approach using density functional theory (DFT) calculations has been investigated to estimate the abundances of first-generation product ions observed using an ion trap mass spectrometer. This has been achieved by application of Boltzmann population theory to electrospray ionisation (ESI)-MS and MS/MS data. RESULTS Tandem ESI-MS data for this preliminary study were used to investigate the internal stabilities of protonated species and their product ions. The calculated relative abundances of 11.3%, 96.5%, and 1.1% for the product ion (m/z 192) of three quinazoline structural isomers are compared with the experimental values of 16%, 90% and 0% observed in the first-generation product ion mass spectra. CONCLUSIONS Close correlation between calculated and experimental data has been demonstrated for these initial data. Applying this approach and establishing fragmentation rules, based on structure specific and common fragmentation behaviour, would improve and expedite the structural elucidation process.
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Shojaei SHR, Morini F, Deleuze MS. Photoelectron and electron momentum spectroscopy of tetrahydrofuran from a molecular dynamical perspective. J Phys Chem A 2013; 117:1918-29. [PMID: 23387306 DOI: 10.1021/jp310722a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The results of experimental studies of the valence electronic structure of tetrahydrofuran employing He I photoelectron spectroscopy as well as Electron Momentum Spectroscopy (EMS) have been reinterpreted on the basis of Molecular Dynamical simulations employing the classical MM3 force field and large-scale quantum mechanical simulations employing Born-Oppenheimer Molecular Dynamics in conjunction with the dispersion corrected ωB97XD exchange-correlation functional. Analysis of the produced atomic trajectories demonstrates the importance of thermal deviations from the lowest energy path for pseudorotation, in the form of considerable variations of the ring-puckering amplitude. These deviations are found to have a significant influence on several outer-valence electron momentum distributions, as well as on the He I photoelectron spectrum.
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Affiliation(s)
- S H Reza Shojaei
- Research Group of Theoretical Chemistry and Molecular Modelling, Hasselt University, Agoralaan Gebouw D, B-3590 Diepenbeek, Belgium
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Abstract
Computational molecular models of chemicals interacting with biomolecular targets provides toxicologists a valuable, affordable, and sustainable source of in silico molecular level information that augments, enriches, and complements in vitro and in vivo efforts. From a molecular biophysical ansatz, we describe how 3D molecular modeling methods used to numerically evaluate the classical pair-wise potential at the chemical/biological interface can inform mechanism of action and the dose-response paradigm of modern toxicology. With an emphasis on molecular docking, 3D-QSAR and pharmacophore/toxicophore approaches, we demonstrate how these methods can be integrated with chemoinformatic and toxicogenomic efforts into a tiered computational toxicology workflow. We describe generalized protocols in which 3D computational molecular modeling is used to enhance our ability to predict and model the most relevant toxicokinetic, metabolic, and molecular toxicological endpoints, thereby accelerating the computational toxicology-driven basis of modern risk assessment while providing a starting point for rational sustainable molecular design.
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25
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Fleury LM, Kosal AD, Masters JT, Ashfeld BL. Cooperative titanocene and phosphine catalysis: accelerated C-X activation for the generation of reactive organometallics. J Org Chem 2012; 78:253-69. [PMID: 23094703 DOI: 10.1021/jo301726v] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The study presented herein describes a reductive transmetalation approach toward the generation of Grignard and organozinc reagents mediated by a titanocene catalyst. This method enables the metalation of functionalized substrates without loss of functional group compatibility. Allyl zinc reagents and allyl, vinyl, and alkyl Grignard reagents were generated in situ and used in the addition to carbonyl substrates to provide the corresponding carbinols in yields up to 99%. It was discovered that phosphine ligands effectively accelerate the reductive transmetalation event to enable the metalation of C-X bonds at temperatures as low as -40 °C. Performing the reactions in the presence of chiral diamines and amino alcohols led to the enantioselective allylation of aldehydes.
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Affiliation(s)
- Lauren M Fleury
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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26
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Garberoglio G. OBGMX: A web-based generator of GROMACS topologies for molecular and periodic systems using the universal force field. J Comput Chem 2012; 33:2204-8. [DOI: 10.1002/jcc.23049] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Revised: 05/29/2012] [Accepted: 06/03/2012] [Indexed: 11/11/2022]
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27
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Andujar SA, Tosso RD, Suvire FD, Angelina E, Peruchena N, Cabedo N, Cortes D, Enriz RD. Searching the "biologically relevant"conformation of dopamine: a computational approach. J Chem Inf Model 2011; 52:99-112. [PMID: 22146008 DOI: 10.1021/ci2004225] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We report here an exhaustive and complete conformational study on the conformational potential energy hypersurface (PEHS) of dopamine (DA) interacting with the dopamine D2 receptor (D2-DR). A reduced 3D model for the binding pocket of the human D2-DR was constructed on the basis of the theoretical model structure of bacteriorhodopsin. In our reduced model system, only 13 amino acids were included to perform the quantum mechanics calculations. To obtain the different complexes of DA/D2-DR, we combined semiempirical (PM6), DFT (B3LYP/6-31G(d)), and QTAIM calculations. The molecular flexibility of DA interacting with the D2-DR was evaluated from potential energy surfaces and potential energy curves. A comparative study between the molecular flexibility of DA in the gas phase and at D2-DR was carried out. In addition, several molecular dynamics simulations were carried out to evaluate the molecular flexibility of the different complexes obtained. Our results allow us to postulate the complexes of type A as the "biologically relevant conformations" of DA. In addition, the theoretical calculations reported here suggested that a mechanistic stepwise process takes place for DA in which the protonated nitrogen group (in any conformation) acts as the anchoring portion, and this process is followed by a rapid rearrangement of the conformation allowing the interaction of the catecholic OH groups.
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Affiliation(s)
- Sebastian A Andujar
- Departamento de Química, Universidad Nacional de San Luis, Chacabuco 915, 5700 San Luis, Argentina
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28
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Smith K, Bruns M, Stoliarov S, Nyden M, Ezekoye O, Westmoreland P. Assessing the effect of molecular weight on the kinetics of backbone scission reactions in polyethylene using Reactive Molecular Dynamics. POLYMER 2011. [DOI: 10.1016/j.polymer.2011.04.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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29
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Affiliation(s)
- Julie Grouleff
- Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Frank Jensen
- Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
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30
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Pandit D, Roosma W, Misra M, Gilbert KM, Skawinski WJ, Venanzi CA. Conformational analysis of piperazine and piperidine analogs of GBR 12909: stochastic approach to evaluating the effects of force fields and solvent. J Mol Model 2010; 17:181-200. [PMID: 20414792 DOI: 10.1007/s00894-010-0712-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Accepted: 03/16/2010] [Indexed: 11/29/2022]
Abstract
Analogs of the flexible dopamine reuptake inhibitor, GBR 12909 (1), may have potential utility in the treatment of cocaine abuse. As a first step in the 3D-QSAR modeling of the dopamine transporter (DAT)/serotonin transporter (SERT) selectivity of these compounds, we carried out conformational analyses of two analogs of 1: a piperazine (2) and a related piperidine (3). Ensembles of conformers consisting of local minima on the potential energy surface of the molecule were generated in the vacuum phase and in implicit solvent by random search conformational analysis using the Tripos and MMFF94 force fields. Some differences were noted in the conformer populations due to differences in the treatment of the tertiary amine nitrogen and ether oxygen atom types by the force fields. The force fields also differed in their descriptions of internal rotation around the C(sp³)-O(sp³) bond proximal to the bisphenyl moiety. Molecular orbital calculations at the HF/6-31G(d) and B3LYP/6-31G(d) levels of C-O internal rotation in model compound (5), designed to model the effect of the proximity of the bisphenyl group on C-O internal rotation, showed a broad region of low energy between -60° to 60° with minima at both -60° and 30° and a low rotational barrier at 0°, in closer agreement with the MMFF94 results than the Tripos results. Molecular mechanics calculations on model compound (6) showed that the MMFF94 force field was much more sensitive than the Tripos force field to the effects of the bisphenyl moiety on C-O internal rotation.
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Affiliation(s)
- Deepangi Pandit
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, 323 King Blvd., Newark, NJ 07102-1982, USA
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31
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Viji SN, Prasad PA, Gautham N. Protein-ligand docking using mutually orthogonal Latin squares (MOLSDOCK). J Chem Inf Model 2010; 49:2687-94. [PMID: 19968302 DOI: 10.1021/ci900332a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The theoretical prediction of the association of a flexible ligand with a protein receptor requires efficient sampling of the conformational space of the ligand. Several docking methodologies are currently available. We have proposed a docking technique that performs well at low computational cost. The method uses mutually orthogonal Latin squares to efficiently sample the docking space. A variant of the mean field technique is used to analyze this sample to arrive at the optimum. The method has been previously applied to search through both the conformational space of a peptide as well its docking space. Here we extend this method to simultaneously identify both the low energy conformation as well as a high scoring docking mode for the small organic ligand molecules. Application of the method to 45 protein-ligand complexes, in which the number of rotatable torsions varies from 2 to 19, and comparisons with AutoDock 4.0, showed that the method works well.
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Affiliation(s)
- S Nehru Viji
- CAS in Crystallography and Biophysics, University of Madras, Chennai-600025, India
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Butts CP, Filali E, Lloyd-Jones GC, Norrby PO, Sale DA, Schramm Y. Structure-Based Rationale for Selectivity in the Asymmetric Allylic Alkylation of Cycloalkenyl Esters Employing the Trost ‘Standard Ligand’ (TSL): Isolation, Analysis and Alkylation of the Monomeric form of the Cationic η3-Cyclohexenyl Complex [(η3-c-C6H9)Pd(TSL)]+. J Am Chem Soc 2009; 131:9945-57. [DOI: 10.1021/ja8099757] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Craig P. Butts
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K., and Department of Chemistry, University of Gothenburg, Kemigården 4, SE-412 96 Göteborg, Sweden
| | - Emane Filali
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K., and Department of Chemistry, University of Gothenburg, Kemigården 4, SE-412 96 Göteborg, Sweden
| | - Guy C. Lloyd-Jones
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K., and Department of Chemistry, University of Gothenburg, Kemigården 4, SE-412 96 Göteborg, Sweden
| | - Per-Ola Norrby
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K., and Department of Chemistry, University of Gothenburg, Kemigården 4, SE-412 96 Göteborg, Sweden
| | - David A. Sale
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K., and Department of Chemistry, University of Gothenburg, Kemigården 4, SE-412 96 Göteborg, Sweden
| | - York Schramm
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, U.K., and Department of Chemistry, University of Gothenburg, Kemigården 4, SE-412 96 Göteborg, Sweden
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Zorn D, Lin VSY, Pruski M, Gordon MS. An Interface between the Universal Force Field and the Effective Fragment Potential Method. J Phys Chem B 2008; 112:12753-60. [DOI: 10.1021/jp8049729] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Deborah Zorn
- Ames Laboratory and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Victor S.-Y. Lin
- Ames Laboratory and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Marek Pruski
- Ames Laboratory and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Mark S. Gordon
- Ames Laboratory and Department of Chemistry, Iowa State University, Ames, Iowa 50011
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Steinmetz WE, Robustelli P, Edens E, Heineman D. Structure and conformational dynamics of trichothecene mycotoxins. JOURNAL OF NATURAL PRODUCTS 2008; 71:589-594. [PMID: 18327910 DOI: 10.1021/np070562x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A combination of NMR spectroscopy and molecular modeling has been employed to characterize the conformation and dynamics of the macrolide ring in verrucarin A and roridin A, two closely related toxins in the trichothecene mycotoxin family. Longitudinal carbon-13 relaxation times demonstrate the relative flexibility of the macrolide ring. The calculations, NOEs, and scalar vicinal coupling constants show that verrucarin A in CDCl 3 and CD 2Cl 2 predominantly adopts a single, well-defined conformation that matches the crystal structure. In contrast, roridin A is present as a mixture of two conformers.
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Affiliation(s)
- Wayne E Steinmetz
- Chemistry Department, Pomona College, Claremont, California 91711, USA.
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35
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36
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Cacciapaglia R, Di Stefano S, Mandolini L, Mencarelli P, Ugozzoli F. Metathesis Reactions of Formaldehyde Acetals – Experimental and Computational Investigation of Isomeric Families of Cyclophanes under Dynamic Conditions. European J Org Chem 2008. [DOI: 10.1002/ejoc.200700906] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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37
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Parallelization of Crystal Calculation for Large-Scale Molecular Crystal Structure Analysis. JOURNAL OF COMPUTER AIDED CHEMISTRY 2008. [DOI: 10.2751/jcac.9.8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Mercandelli P, Sironi A, Resconi L, Camurati I. Comparing propene polymerization with 1-butene polymerization catalyzed by MAO-activated C2- and C1-symmetric zirconocenes: An experimental and computational study on the influence of olefin size on stereoselectivity. J Organomet Chem 2007. [DOI: 10.1016/j.jorganchem.2007.06.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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39
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Kaminský J, Jensen F. Force Field Modeling of Amino Acid Conformational Energies. J Chem Theory Comput 2007; 3:1774-88. [DOI: 10.1021/ct700082f] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jakub Kaminský
- Department of Physics and Chemistry, University of Southern Denmark, DK-5230 Odense, Denmark, and Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 166 10 Prague, Czech Republic
| | - Frank Jensen
- Department of Physics and Chemistry, University of Southern Denmark, DK-5230 Odense, Denmark, and Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 166 10 Prague, Czech Republic
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40
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Phillips ST, Shair MD. Syntheses of the Eastern Halves of Ritterazines B, F, G, and H, Leading to Reassignment of the 5,5-Spiroketal Stereochemistry of Ritterazines B and F. J Am Chem Soc 2007; 129:6589-98. [PMID: 17469826 DOI: 10.1021/ja0705487] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ritterazine class of natural products comprises 26 compounds-all of which are spiroketal-containing steroidal heterodimers-that inhibit the proliferation of cultured human cancer cell lines with IC50 values in the low nanomolar range. Little is known about their chemistry, cellular target(s), or mechanism(s) of growth inhibition, due primarily to the small amount of material available from natural sources. In this paper we report syntheses of the eastern halves of ritterazines B, F, G, and H and address the energetic and mechanistic aspects of spiroketal equilibration for each. These studies have led to reassignment of the 5,5-spiroketal stereochemistry of ritterazines B and F, and they have enabled us to propose a quantitative description of the natural distribution of these ritterazine compounds.
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Affiliation(s)
- Scott T Phillips
- Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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41
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Wolohan P, Reichert DE. Molecular modeling of hexakis(areneisonitrile)technetium(I), tricarbonyl eta5 cyclopentadienyl technetium and technetium(V)-oxo complexes: MM3 parameter development and prediction of biological properties. J Mol Graph Model 2007; 25:616-32. [PMID: 16769234 DOI: 10.1016/j.jmgm.2006.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 04/26/2006] [Accepted: 04/27/2006] [Indexed: 11/24/2022]
Abstract
Genetic algorithms (GA) were used to develop specific technetium metal-ligand force field parameters for the MM3 force field. These parameters were developed using automated procedures within the program FFGenerAtor from a combination of crystallographic structures and ab initio calculations. These new parameters produced results in good agreement with experiment when tested against a blind validation set. To illustrate the utility of these new force field parameters, quantitative structure-activity relationship (QSAR) models were developed to predict the P-glycoprotein uptake (log10 VI) of a series of hexakis(areneisonitrile)technetium(I) complexes and to predict their biodistribution. The log10 VI QSAR model, built using a training set of 16 Tc(I) isonitrile complexes, exhibited a correlation between the experimental log10 VI and 5 simple descriptors as follows: r2 = 0.94, q2 = 0.93. When applied to an external test set of six Tc(I) isonitrile complexes, the QSAR preformed with great accuracy q2 = 0.78 based on a leave-one-out cross-validation analysis. Further QSAR models were developed to predict the biodistribution of the same set of Tc(I) isonitrile complexes; a QSAR model to predict hepatic uptake exhibited a correlation between the experimental log10(Blood/Liver) with six simple descriptors as follows: r2 = 0.97, q2 = 0.96. A QSAR model to predict renal uptake exhibited a correlation between the experimental log10(Blood/Kidney) and six simple descriptors as follows: r2 = 0.85, q2 = 0.82. When applied to the external test set the QSAR models preformed with great accuracy, q2 = 0.78 and 0.56, respectively.
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Affiliation(s)
- Peter Wolohan
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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42
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Smith KD, Stoliarov SI, Nyden MR, Westmoreland PR. RMDff: A smoothly transitioning, forcefield-based representation of kinetics for reactive molecular dynamics simulations. MOLECULAR SIMULATION 2007. [DOI: 10.1080/08927020601156392] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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43
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Molecular Mechanics Calculated Conformational Energies of Organic Molecules: A Comparison of Force Fields. REVIEWS IN COMPUTATIONAL CHEMISTRY 2007. [DOI: 10.1002/9780470125861.ch4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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44
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Computational Determination of the Relative Free Energy of Binding – Application to Alanine Scanning Mutagenesis. ACTA ACUST UNITED AC 2007. [DOI: 10.1007/1-4020-5372-x_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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45
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Isopo A, Caminiti R, D'Amato R, Furlani A, Russo MV. Energy Dispersive X-ray Diffraction (Edxd) Investigation Of Amorphous Poly(phenylacetylene) (Ppa). J MACROMOL SCI B 2006. [DOI: 10.1081/mb-120023558] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Alessandro Isopo
- a Dipartimento di Chimica , INFM Istituto Nazionale di Fisica della Materia , Roma, Italy
| | - Ruggero Caminiti
- a Dipartimento di Chimica , INFM Istituto Nazionale di Fisica della Materia , Roma, Italy
| | - Rosaria D'Amato
- b Dipartimento di Chimica , Università degli Studi di Roma “La Sapienza” , Roma, Italy
| | - Anita Furlani
- b Dipartimento di Chimica , Università degli Studi di Roma “La Sapienza” , Roma, Italy
| | - Maria V. Russo
- b Dipartimento di Chimica , Università degli Studi di Roma “La Sapienza” , Roma, Italy
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46
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Strand D, Norrby PO, Rein T. Divergence en Route to Nonclassical Annonaceous Acetogenins. Synthesis of Pyranicin and Pyragonicin†. J Org Chem 2006; 71:1879-91. [PMID: 16496972 DOI: 10.1021/jo052233k] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Syntheses of the nonclassical annonaceous acetogenins, pyranicin, and pyragonicin from common late-stage intermediates are presented. The construction of key elements relies on asymmetric HWE reactions, including the desymmetrization of a meso-dialdehyde and a parallel kinetic resolution of a racemic aldehyde. A stereoconvergent Pd-catalyzed substitution serves to install the C4 stereocenter in protected form with different orthogonal protective groups. A divergent strategy to form 1,4- and 1,6-diols, employing stereoselective Zn-mediated alkynylations, is used for completion of the core structures. Notably, the stereoselective coupling reaction toward pyragonicin proceeds with highly functionalized fragments. The methodology is further expanded by a divergent synthesis of all stereoisomers of the 2,3,6-trisubstituted tetrahydropyran subunit.
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Affiliation(s)
- Daniel Strand
- KTH Chemical Science and Engineering, Organic Chemistry, SE-100 44 Stockholm, Sweden
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47
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Low CMR, Buck IM, Cooke T, Cushnir JR, Kalindjian SB, Kotecha A, Pether MJ, Shankley NP, Vinter JG, Wright L. Scaffold hopping with molecular field points: identification of a cholecystokinin-2 (CCK2) receptor pharmacophore and its use in the design of a prototypical series of pyrrole- and imidazole-based CCK2 antagonists. J Med Chem 2005; 48:6790-802. [PMID: 16250638 DOI: 10.1021/jm049069y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new molecular modeling approach has been used to derive a pharmacophore of the potent and selective cholecystokinin-2 (CCK(2)) receptor antagonist 5 (JB93182), based on features shared with two related series. The technique uses "field points" as simple and effective descriptions of the electrostatic and van der Waals maxima and minima surrounding a molecule equipped with XED (extended electron distribution) charges. Problems associated with the high levels of biliary elimination of 5 in vivo required us to design a compound with significantly lower molecular weight without sacrificing its nanomolar levels of in vitro activity. Two new series of compounds were designed to mimic the arrangement of field points present in the pharmacophore rather than its structural elements. In a formal sense, two of the three amides in 5 were replaced with either a simple pyrrole or imidazole, while some features thought to be essential for the high levels of in vitro activity of the parent compounds were retained and others deleted. These compounds maintained activity and selectivity for this receptor over CCK(1). In addition, the reduction in molecular weight coupled with lower polarities greatly reduced levels of biliary elimination associated with 5. This makes them good lead compounds for development of drug candidates whose structures are not obviously related to those of the parents and represents the first example of scaffold hopping using molecular field points.
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Affiliation(s)
- Caroline M R Low
- James Black Foundation, 68 Half Moon Lane, London SE24 9JE, U.K.
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48
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Wolohan P, Yoo J, Welch MJ, Reichert DE. QSAR studies of copper azamacrocycles and thiosemicarbazones: MM3 parameter development and prediction of biological properties. J Med Chem 2005; 48:5561-9. [PMID: 16107156 PMCID: PMC2566539 DOI: 10.1021/jm0501376] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Genetic algorithms (GA) were used to develop specific copper metal-ligand force field parameters for the MM3 force field, from a combination of crystallographic structures and ab initio calculations. These new parameters produced results in good agreement with experiment and previously reported copper metal-ligand parameters for the AMBER force field. The MM3 parameters were then used to develop several quantitative structure-activity relationship (QSAR) models. A successful QSAR for predicting the lipophilicity (log P(ow)) of several classes of Cu(II)-chelating ligands was built using a training set of 32 Cu(II) radiometal complexes and 6 simple molecular descriptors. The QSAR exhibited a correlation between the predicted and experimental log P(ow) with an r(2) = 0.95, q(2) = 0.92. When applied to an external test set of 11 Cu(II) complexes, the QSAR preformed with great accuracy; r(2) = 0.93 and a q(2) = 0.91 utilizing a leave-one-out cross-validation analysis. Additional QSAR models were developed to predict the biodistribution of a smaller set of Cu(II) bis(thiosemicarbazone) complexes.
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Affiliation(s)
- Peter Wolohan
- Washington University School of Medicine, St. Louis, Missouri 63110, USA
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49
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Kuhn B, Gerber P, Schulz-Gasch T, Stahl M. Validation and use of the MM-PBSA approach for drug discovery. J Med Chem 2005; 48:4040-8. [PMID: 15943477 DOI: 10.1021/jm049081q] [Citation(s) in RCA: 351] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The MM-PBSA approach has become a popular method for calculating binding affinities of biomolecular complexes. Published application examples focus on small test sets and few proteins and, hence, are of limited relevance in assessing the general validity of this method. To further characterize MM-PBSA, we report on a more extensive study involving a large number of ligands and eight different proteins. Our results show that applying the MM-PBSA energy function to a single, relaxed complex structure is an adequate and sometimes more accurate approach than the standard free energy averaging over molecular dynamics snapshots. The use of MM-PBSA on a single structure is shown to be valuable (a) as a postdocking filter in further enriching virtual screening results, (b) as a helpful tool to prioritize de novo design solutions, and (c) for distinguishing between good and weak binders (DeltapIC(50) > or = 2-3), but rarely to reproduce smaller free energy differences.
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Affiliation(s)
- Bernd Kuhn
- Molecular Design, Pharmaceutical Division, F. Hoffmann-La Roche AG, Basel, Switzerland.
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50
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Wong RL, Williams ER, Counterman AE, Clemmer DE. Evaluation of ion mobility spectroscopy for determining charge-solvated versus salt-bridge structures of protonated trimers. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2005; 16:1009-19. [PMID: 15914022 DOI: 10.1016/j.jasms.2005.03.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2004] [Revised: 03/21/2005] [Accepted: 03/24/2005] [Indexed: 05/02/2023]
Abstract
The cross sections of five different protonated trimers consisting of two base molecules and trifluoroacetic acid were measured by using ion mobility spectrometry. The gas-phase basicities of these five base molecules span an 8-kcal/mol range. These cross sections are compared with those determined from candidate low-energy salt-bridge and charge-solvated structures identified by using molecular mechanics calculations using three different force fields: AMBER*, MMFF, and CHARMm. With AMBER*, the charge-solvated structures are all globular and the salt-bridge structures are all linear, whereas with CHARMm, these two forms of the protonated trimers can adopt either shape. Globular structures have smaller cross sections than linear structures. Conclusions about the structure of these protonated trimers are highly dependent on the force field used to generate low-energy candidate structures. With AMBER*, all of the trimers are consistent with salt-bridge structures, whereas with MMFF the measured cross sections are more consistent with charge-solvated structures, although the assignments are ambiguous for two of the protonated trimers. Conclusions based on structures generated by using CHARMm suggest a change in structure from charge-solvated to salt-bridge structures with increasing gas-phase basicity of the constituent bases, a result that is most consistent with structural conclusions based on blackbody infrared radiative dissociation experiments for these protonated trimers and theoretical calculations on the uncharged base-acid pairs.
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Affiliation(s)
- Richard L Wong
- Department of Chemistry, University of California, Berkeley, California 94720, USA
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